// Copyright (C) Kumo inc. and its affiliates.
// Author: Jeff.li lijippy@163.com
// All rights reserved.
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as published
// by the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program.  If not, see <https://www.gnu.org/licenses/>.
//
#pragma once

#define XXH_INLINE_ALL
#include <xxhash.h>

#include <pollux/functions/udf.h>
#include <pollux/type/type.h>

namespace kumo::pollux::functions {
    /// xxhash64(bigint) → bigint
    /// Return a xxhash64 of input Date
    template<typename T>
    struct XxHash64BigIntFunction {
        POLLUX_DEFINE_FUNCTION_TYPES(T);

        MELON_ALWAYS_INLINE
        void call(out_type<int64_t> &result, const arg_type<int64_t> &input) {
            result = XXH64(&input, sizeof(input), 0);
        }
    };

    // combine_hash(bigint, bigint) → bigint
    template<typename T>
    struct CombineHashFunction {
        POLLUX_DEFINE_FUNCTION_TYPES(T);

        MELON_ALWAYS_INLINE
        void call(
            out_type<int64_t> &result,
            const arg_type<int64_t> &previousHashValue,
            const arg_type<int64_t> &input) {
            result = static_cast<int64_t>(
                31 * static_cast<uint64_t>(previousHashValue) +
                static_cast<uint64_t>(input));
        }
    };
} // namespace kumo::pollux::functions
